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  <head>
    <meta charset="UTF-8">
    <title>Document</title>
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  <body>
    <script>
      var score = 90;
      if (score >= 90) {
        console.log('优秀');
      } else if (score >= 80) {
        console.log('良好');
      } else if (score >= 70) {
        console.log('中等');
      } else if (score >= 60) {
        console.log('及格');
      } else {
        console.log('不及格');
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